The brain is made up of nerve cells, called
neurons, and chemicals, called neurotransmitters. An imbalance of one
neurotransmitter, dopamine, is thought to cause the symptoms of schizophrenia.
Recent studies suggest that serotonin, another neurotransmitter, may also play a
significant role in causing the symptoms of schizophrenia.Brain activity
differs in a brain with schizophrenia and a brain without schizophrenia. In the
brain with schizophrenia, far more neurotransmitters are released between
neurons. Thus, the symptoms of schizophrenia occur.

Dopamine

The
"dopamine hypothesis" has been the main theory regarding the cause of the
symptoms of schizophrenia. Researchers believe that many of the symptoms of
schizophrenia are a result of excess of dopamine in the brain. Anti psychotic
medications block dopamine transmission and are used to treat and improve the
symptoms of schizophrenia.

Serotonin

New theories suggest that the
neurotransmitter serotonin may also play a role in causing the symptoms of
schizophrenia. Some anti psychotic medications treat symptoms of schizophrenia
by blocking dopamine and serotonin transmissions. Many patients who have not
been helped by "dopamine only” medications have been helped by medications that
affect both dopamine and serotonin transmissions, such as Clozaril, Risperdal
and Zyprexa.